Integrated circuits (ICs) may include analog and digital electronic circuits on a flat semiconductor substrate, such as a silicon wafer. Microscopic transistors are printed onto the substrate using photolithography techniques to produce complex circuits of billions of transistors in a very small area, making modern electronic circuit design using ICs both low cost and high performance. ICs are produced in assembly lines of factories, termed foundries, which have commoditized the production of ICs, such as complementary metal-oxide-semiconductor (CMOS) ICs. Digital ICs contain billions of transistors arranged in functional and/or logical units on the wafer, and are packaged in a metal, plastic, glass, or ceramic casing. The casing, or package, is connected to a circuit board, such as by using solder. Types of packages may include a leadframe (though-hole, surface mount, chip-carrier, and/or the like), pin grid array, chip scale package, ball grid array, and/or the like, to connect between the IC pads and the circuit board. As used herein, the term IC means the integrated circuit including the package.
Hofmeister et al., “Ball Grid Array (BGA) Solder Joint Intermittency Detection: SJ BIST”, IN IEEE Aerospace Conference, 2008, discusses a sensing method for detecting faults in solder-joint networks belonging to the input/output (I/O) block of Field Programmable Gate Arrays (FPGAs), especially in Ball Grid Array packages. This involves the attachment of a small capacitor to two unused I/O ports as near as possible to the corner of the package. This approach may be suitable for monitoring special bumps to detect intermittent failure but might be inappropriate for monitoring functional bumps.
The foregoing examples of the related art and limitations related therewith are intended to be illustrative and not exclusive. Other limitations of the related art will become apparent to those of skill in the art upon a reading of the specification and a study of the figures.